Investigate replacing "all urls" permissions in the FF and Safari browsers with specific scopes (like the Chrome extension)

Created by: Joelkw

Our chrome extension scopes its permissions asks to only code host urls and Sourcegraph. The Safari and Firefox extensions ask for all urls permissions.

Historically, we think this may be because when we first built these extensions scoping permissions may not have been available, or it might likely be a difference between Chrome letting users add additional sites to their allowlists using the extension itself while FF and Safari may not allow that (and we didn't want to over-lock-it-down).

We should see if it's now feasible to bring the FF and Safari permissions in line with the chrome extensions permissons.